Oxygen-containing heterocyclic fused naphthopyrans

ABSTRACT

This invention relates to novel naphthopyrans having an oxygen-containing heterocyclic group F annelated on the i, j, or k side of the naphthopyran ring, having certain substituents at the 2, 5, and 6 positions of the naphthopyran ring. These naphthopyrans may have the formula (I) presented below:  
                 
 
     These compounds (I) have interesting photochromic properties. Also related to this invention are host materials that contain such naphthopyran compounds, and articles such as ophthalmic lenses or other plastic transparencies that incorporate the naphthopyran compounds.

CROSS REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. ProvisionalApplication No. 60/421,348, filed Oct. 24, 2002 and U.S. ProvisionalApplication No. 60/422,147 filed Oct. 28, 2002, and whose entirecontents are hereby incorporated by reference.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] The present invention relates to novel naphthopyran-typecompounds that have, in particular, photochromic properties. Theinvention also relates to the use of these photochromic compounds inophthalmic articles (goggles, lenses and eye-shields, for example). Theinvention particularly relates to naphthopyrans having anoxygen-containing saturated heterocyclic group fused to the naphthalenering. These naphthopyrans have two intense absorption bands in thevisible light range, and are particularly suitable for use inphotochromic articles, such as eyeglass lenses, which have a brown ordriver activated color.

[0004] 2. Background of the Art

[0005] Photochromism generally concerns the ability of a compound toreversibly change color under different light conditions. One particulartype of photochromic phenomenon concerns the reversible change in colorof a compound from an original color to a different color when thecompound is exposed to a source of ultraviolet radiation, such as solarradiation or light radiated from a mercury or xenon lamp. Thephotochromic compound fades to the original color within a period oftime after the photochromic compound is isolated from the ultravioletradiation, such as by placing the compound in a dark room.

[0006] Photochromic compounds find applications in various fields, suchas for the manufacture of ophthalmic lenses, contact lenses, solarprotection glasses, goggles, sun screens, filters, camera optics,photographic apparatus optics or other optical devices and observationdevices, glazing, decorative objects, currency elements and even forinformation storage by optical inscription (coding). For example,photochromic compounds, such as naphthopyrans, are incorporated intoplastic ophthalmic lenses to effect color changes in the lenses when thelenses are exposed to particular lighting conditions. Additionally,different photochromic compounds may be blended together to create acolor effect that is different from respective color effects of theindividual photochromic compounds. As an example, a first photochromiccompound that turns orange or red when activated by light and a secondphotochromic compound that turns blue when activated by light may beblended together to form a photochromic mixture that produces a shade ofgray when activated by light.

[0007] Amongst the numerous photochromic compounds described in theprior art, naphthopyrans and larger ring systems derived from themreceived the most intensive investigations due to their suitableproperties (fatigue, fading rate, color, temperature dependence) for usein eyeglass lenses. The simplest naphthopyran photochromic compounds arerepresented by the formula below:

[0008] Attempts were made to achieve improvements by using differentsubstituents at various positions, especially on the naphthalene core.The improvements include proper fading rate, desired color, betterfatigue, etc. One of the important improvements is for a naphthopyran toprovide a blended color hue. As aforementioned, to give eyeglass lensesa neutral gray or brown color, it may necessitate the use of at leasttwo photochromic compounds of different colors, i.e., two separatecompounds having distinct maximal absorption wavelengths in the visibleregion of the electromagnetic spectrum. However, the use of combinationsof photochromic compounds imposes other requirements on both theindividual photochromic compounds and the groups of photochromiccompounds. In particular, the coloration and discoloration kinetics ofthe (two or more) combined active photochromic compounds must beessentially identical. The same applies for their stability with time,and also for their compatibility with a single plastic or inorganicsupport.

[0009] It is thus highly desirable to obtain photochromic compounds thathave a blended color hue provided by two or more distinct absorptionbands in the visible region. With such photochromic compounds it ispossible to use only one compound for the desired color (e.g., gray orbrown), or at least to require minimum amount of complementary colorcompound.

[0010] U.S. Pat. No. 5,645,767 discloses photochromicindeno[2,1-f]naphtho[1,2-b]pyrans having a blue/gray activated color. Ablue/gray color will be perceived when there is a major absorption ofvisible light in the 580-620 nm range (Band B thereafter referring tothe longer wavelengths) coupled with a minor absorption in the 420-500nm range (Band A thereafter referring to the shorter wavelengths).

[0011] U.S. Pat. No. 6,096,246 (incorporated by reference) describesnaphtho[1,2-b]pyrans having alkoxy groups as substituents at the 7- and9-positions of the naphthopyran ring. The activated forms of thesecompounds exhibit two intense absorption bands in the visible lightrange. It is reported that the optical density of Band A in some casesis higher than the optical density of Band B, but in the majority ofcases Band A is of lower optical density than Band B.

[0012] U.S. Pat. No. 6,146,554 (incorporated by reference) disclosesphotochromic indeno[2,1-f]naphtho[1,2-b]pyrans having a green activatedcolor. A greenish color will be perceived when there is a majorabsorption of visible light in the 580-620 nm range coupled with a majorabsorption of roughly equal intensity in the 400480 nm range. U.S. Pat.No. 6,248,264 (incorporated by reference) describes naphtho[1,2-b]pyranshaving amino functional groups as substituents at the 7- or 9-positionsof the naphthopyran ring. These compounds are disclosed as exhibiting abrown or red/brown activated color. A red/brown color will be perceivedwhen there is a major absorption of visible light in the 420-500 nmrange coupled with a minor absorption in the 520-560 nm range.

[0013] U.S. Pat. Nos. 6,296,785 and 6,348,6043 (incorporated byreference) disclose indeno[2,1-f]naphtho[1,2-b]pyrans andnaphtho[1,2-b]pyrans, respectively, having two adjacent moderate tostrong electron donor substituents at the 6 and 7 positions ofindeno[2,1-f]naphtho[1,2-b]pyrans and the 8 and 9 positions ofnaphtho[1,2-b]pyrans. The activated forms of these compounds exhibit twointense absorption bands in the visible light range. In the majority ofcases Band A (420-500 nm) is of stronger optical density than Band B(480-620 nm)making them suitable for use in photochromic articles havinga brown activated color.

[0014] U.S. Pat. No. 6,353,102 (incorporated by reference) describesnaphtho[1,2-b]pyrans having carbonyl functional groups as substituentsat the 6-position of the naphthopyran ring. These compounds aredisclosed as also exhibiting two absorption bands in the visible lightrange. The relative intensity of the two bands depends on othersubstituents on the ring.

[0015] From the above description, it is apparent that photochromiccompounds having two absorption bands can be obtained by selectingcertain substituents at the naphthopyran ring, especially at the 6 to 9positions of the naphtho portion. Although some prior art referencesteach how to select substituents, it seems that such prior artreferences are incomplete and do not achieve the formulative results ofthe present invention.

[0016] Therefore, it is an object of this invention to provide novelseries of photochromic compounds that exhibit two intense absorptionbands in the visible range wherein the relative intensity between Band Aand Band B is greater than unity. These photochromic compounds will beespecially useful in making brown or driver (red-brown) photochromicarticles such as eyeglass lenses with a single compound or minimum useof a complementary color compound.

[0017] All publications and patents referred to in this application arehereby incorporated by reference.

DESCRIPTION OF THE INVENTION

[0018] An objective of this invention is achieved by preparing a novelfamily of naphthopyran compounds having a central nucleus of theformula:

[0019] wherein F is a 5- to 7-member saturated heterocyclic ring groupfused to the i or j side of the naphthopyran ring containing one oxygenthat is atom directly connected to the 7-, 8- or 9-position;

[0020] R₆ represents

[0021] i. a C1-C6 alkyl, alkoxy,

[0022] ii. a —C(O)R group, wherein R is selected from hydrogen, hydroxy,alkyl, alkoxy,

[0023] iii. an aryl or heteroaryl group which comprises in its basicstructure (that is, in its ring atoms, the rings comprising 5, 6 or 7atoms) 6 to 24 carbon atoms or 4 to 24 carbon atoms respectively and atleast one heteroatom selected from sulfur, oxygen and nitrogen; thebasic structure being optionally substituted with at least onesubstituent selected from:

[0024] iv. a halogen atom (e.g., fluorine, chlorine and bromine),

[0025] v. a hydroxy group,

[0026] vi. a linear or branched alkyl group comprising 1 to 12 carbonatoms,

[0027] vii. a linear or branched alkoxy group comprising 1 to 12 carbonatoms,

[0028] viii. a haloalkyl or haloalkoxy group corresponding to the(C1-C12) alkyl or alkoxy groups above respectively which are substitutedwith at least one halogen atom, and notably a fluoroalkyl group of thistype,

[0029] ix. a linear or branched alkenyl group comprising 2 to 12 carbonatoms, and notably a vinyl group or an allyl group,

[0030] x. an —NH2 group,

[0031] xi. an —NHR8 group, R8 representing a linear or branched alkylgroup comprising 1 to 6 carbon atoms,

[0032] xii. a

[0033]  group, in which R₉ and R₁₀, which are the same or different,independently representing a linear or branched alkyl group comprising 1to 6 carbon atoms, or representing (together with the nitrogen atom towhich they are bound) a 5- to 7-membered ring which can comprise atleast one other heteroatom selected from oxygen, sulfur and nitrogen,said nitrogen being optionally substituted with a group that is a linearor branched alkyl group comprising 1 to 6 carbon atoms,

[0034] xiii. a methacryloyl group or an acryloyl group,

[0035] xiv. a polyether, polyamide, polycarbonate, polycarbamate,polyurea or polyester residue;

[0036] R₅ represents:

[0037] i. a hydroxy,

[0038] ii. a halogen, and notably fluorine, chlorine or bromine,

[0039] iii. a linear or branched alkyl group which comprises 1 to 12carbon atoms (advantageously 1 to 6 carbon atoms),

[0040] iv. a cycloalkyl group comprising 3 to 12 carbon atoms,

[0041] v. a linear or branched alkoxy group comprising 1 to 12 carbonatoms (most advantageously 1 to 6 carbon atoms),

[0042] vi. a haloalkyl, halocycloalkyl, or haloalkoxy groupcorresponding to the alkyl, cycloalkyl, alkoxy groups aboverespectively, which are substituted with at least one halogen atom,notably selected from fluorine, chlorine and bromine,

[0043] vii. a linear or branched alkenyl or alkynyl group comprising1-12 carbon atoms, preferably a vinyl or allyl group,

[0044] viii. a linear or branched alkenyloxy or alkynyloxy groupcomprising 1-12 carbon atoms, preferably an allyloxy group,

[0045] ix. an aryl or heteroaryl group having the same definition as R₆given supra,

[0046] x. an aralkyl or heteroaralkyl group, the alkyl group, which islinear or branched, comprising 1 to 4 carbon atoms, and the aryl andheteroaryl groups having the same definitions as R₆ given supra,

[0047] xi. an amine or amide group: —NH₂, —NHR₈, —CONH₂, —

[0048] CONHR₈,

[0049] R₈, R₉, and R₁₀ having their respective definitions given abovefor the amine substituents of the values R₆,

[0050] xii. a —C(R₁₁)₂X group, wherein X is —CN, halogen, hydroxy,alkoxy, benzoyloxy, C1-C6 acyloxy, amino, C1-C6 mono-alklamino, C1-C6dialkyl amino, morpholino, piperidino, 1-indolinyl, pyrrolidyl, ortrimethylsilyloxy, R₁₆ is hydrogen, C1-C6 alkyl, phenyl or naphthyl withC1-C6 alkyl or C1-C6 alkoxy substituents,

[0051] xiii. an —OCOR₁₂ or —COOR₁₂ group, R₁₂ representing a straight orbranched alkyl group comprising 1 to 6 carbon atoms, or a cycloalkylgroup comprising 3 to 7 carbon atoms, or a phenyl group, optionallysubstituted with at least one of the substituents listed above withinthe values in the definitions of R₆,

[0052] xiv. a methacryloyl group or an acryloyl group, an epoxy grouphaving the formula,

[0053]  in which k=1,2 or 3,

[0054] xv. a polyether, polyamide, polycarbonate, polycarbamate,polyurea or polyester residue;

[0055] R₁ and R₂, which are identical or different, independentlyrepresent:

[0056] i. a hydrogen,

[0057] ii. a linear or branched alkyl group which comprises 1 to 12carbon atoms (with or without substitution),

[0058] iii. a cycloalkyl group which comprises 3 to 12 carbon atoms,

[0059] iv. an aryl or heteroaryl group as R₆ defined supra,

[0060] v. an aralkyl or heteroaralkyl group, the alkyl group, which islinear or branched, comprising 1 to 4 carbon atoms and the aryl andheteroaryl groups having the definitions given above, or

[0061] vi. the two substituents R1 and R2 together forming ring groupsuch as those represented by an adamantyl, norbornyl, fluorenylidene,5,5- or 10,10-di(C1-C6)alkylanthracenylidene, 5 (or 10)-(C1-C6)alkyl-5(or 10)-OH (or OR₁₅)anthracenylidene orspiro(C5-C6)cycloalkylanthracenylidene ring group; said ring group beingoptionally substituted with at least one of the substituents listedabove in the definitions for R₁, R₂; said ring group being optionallysubstituted with two adjacent groups that form a 5- to 6-member aromaticor non-aromatic ring which can comprise at least one heteroatom selectedfrom oxygen, sulfur, and nitrogen;

[0062] each R₇ group can be the same or different, independentlyrepresenting

[0063] i. a hydrogen,

[0064] ii. a linear, branched, or cyclic alkyl group,

[0065] iii. a linear, branched, or cyclic alkoxy group,

[0066] iv. a linear or branched alkenyl or alkynyl group,

[0067] v. a linear or branched alkenyloxy or alkynyloxy group,

[0068] vi. an aryl or heteroaryl group having the same definition asthat given supra for R₆,

[0069] vii. two of the R₇ groups, which are adjacent or bonded to thesame carbon atom in the group F, form a 5- to 7-membered non-aromaticring which may comprise at least one hetroatom selected from the groupconsisting of oxygen, sulfur, and nitrogen, and

[0070] viii. m is an integer of 0 to 6.

[0071] The term “group” has established meanings according to thepractice of the present invention. Where the term “group” is used, thechemical unit described is intended to include and allow forsubstituents consistent with the primary chemical unit. For example,where the term alkyl group is used, that term is intended to includeclassic alkyl materials such as methyl, ethyl, propyl, butyl, hexyl,octyl, iso-octyl, dodecyl, cyclohexyl and the like, and is also intendedto include alkyl units with substitution thereon consistent with theunderlying nature of an alkyl unit, such as hydroxymethyl, bromoethyl,dichloropropyl, 1,2,3,4-tetrachlotobutyl, omega-cyanohexyl and the like.Where the term “alkyl moiety” is used, no substitution is allowed.

[0072] Where the term ‘group’ is used in the practice of the presentinvention, those terms refer to the capability of the structure to havesubstitution, or no substitution on the chemical unit. The term ‘group’refers to any chemical structure, while the term ‘central nucleus’refers specifically to a ring structure as the core chemical moiety. Forexample, an ‘alkyl group’ includes unsubstituted n-alkyl, iso-alkyl,methyl ethyl, octyly, iso-octyl, docecyl, and the like, and substitutedalkyl such as hydroxymethyl, 1-chloroethyl, 2-cyano-butyl,3-ethyl-4-hexyl, omega-carboxy-pentyl, and the like. Where the term‘moiety’ is used, as in the term alkyl moiety, for example, that termrefers to only unsubstituted chemical units. Similarly, where the term‘central nucleus’ is used, such as in the central nucleus of a naphthyl,any substituent may be present on the central nucleus of the naphthylgroup, such as 1-methyl-, 2-chloro-, 2,4-dimethoxy-, 2,2′-dimethoxy-,and the like. Where the term having a structure of the specific formulais used, no substitution is allowed beyond that of the describedformula.

[0073] Among the substituents that can be considered for the compoundsof formula (I) according to the invention, groups should be consideredthat comprise and/or form at least one function which can be polymerizedand/or crosslinked, which groups are preferably selected from thefollowing list including but not limited to: alkenyl, advantageouslyvinyl, methacryloyl, acryloyl, acryloxyalkyl, methacryloxyalkyl orepoxy.

[0074] Thus, the photochromic compounds according to the invention canbe monomers, of different types or not, that can react with each otheror with other comonomers to form homopolymers and/or copolymers thatbear a photochromic functionality and possess mechanical properties ofmacromolecules. It follows that one of the objects of the presentinvention consists of these homopolymers or copolymers comprising(co)monomers and/or of crosslinked compounds, that, at least in part,consist of photochromic compounds (I) according to the invention.

[0075] In the same general concept, the above-mentioned compounds (I)can be crosslinking agents that have one or more reactive functionscapable of allowing the formation of bridges between chains of polymersof photochromic nature or not. The crosslinked compounds that can beobtained in this manner also are a part of the present invention.

[0076] Amongst such compounds according to formula (I), preferredphotochromic are those which have the formula below: in which:

[0077] m and n are integers of 1 or 2,

[0078] R′₁ and R′₂, same or different, represent

[0079] i. a hydrogen,

[0080] ii. a linear, branched, or cyclic alkyl,

[0081] iii. an alkyoxy with the alkyl portion being linear, branched, orcyclic,

[0082] iv. an unsubstituted, mono- or di-substituted aryl,

[0083] v. an aryloxy with the aryl being unsubstituted, mono- ordi-substituted;

[0084] R₅ represents

[0085] i. a linear, branched, or cyclic alkyl group,

[0086] ii. a linear or branched alkenyl or alkynyl group,

[0087] iii. a —C(R₁₁)₂X group, wherein X is hydroxy, alkoxy, benzoyloxy,C1-C6 acyloxy,

[0088] iv. an optionally substituted phenyl or benzyl group,

[0089] v. a —COR₁₂, or —COOR₁₂ group, R₁₂ representing a linear,branched, or cyclic alkyl group comprising 1 to 6 carbon atoms;

[0090] R₆ represents an unsubstituted, mono-, di- or tri-substitutedaromatic or hetero-aromatic group selected from phenyl, naphthyl,pyridyl, furanyl, benzofuranyl, thenyl, benzothienyl;

[0091] R₇ represents

[0092] i. a hydrogen,

[0093] ii. a linear, branched, or cyclic alkyl group,

[0094] iii. a linear, branched, or cyclic alkoxy group,

[0095] iv. a linear or branched alkenyl or alkynyl group,

[0096] v. a linear or branched alkenyloxy or alkynyloxy group,

[0097] vi. an aryl or heteroaryl group having the same definition asthat given supra for R₆,

[0098] vii. two of the R₇ groups, which are adjacent or bonded to thesame carbon atom in the group F, form a 5- to 7-membered non-aromaticring which may comprise at least one hetroatom selected from the groupconsisting of oxygen, sulfur, and nitrogen, and

[0099] viii. m is an integer of 0 to 2.

[0100] The person skilled in the art will obviously have understood thatthe branched alkyl, alkoxy, alkenyl, alkenyloxy groups, and cyclic alkylas defined above, comprise a sufficient number of carbon in order to bebranched or cyclic.

[0101] These compounds of the invention present particularlyadvantageous photochromic properties, such as, having strong colorationability with two intense absorption bands in the visible range. They areparticularly useful in making brown or driver colored eyeglass lenses.These compounds are also preferably stable and compatible with matricesmade of at least one organic polymer or mineral material (e.g., inertinorganic binder), both in the form included in the matrix and in theform of a coating.

[0102] General Synthetic Procedure for Preparation of the Compounds

[0103] The compounds of the invention can be obtained by thecondensation of a derivative of 1-naphthol that is suitably substitutedand a derivative of propargyl alcohol. The condensation can be carriedout in organic solvents, particularly non-polar solvents such astoluene, xylene or tetrahydrofuran and, optionally, in the presence of acatalyst, acid catalysts, and especially acid catalysts such asfluorinated organic acid catalysts, p-toluenesulfonic acid, chloroaceticacid or acid aluminic acid):

[0104] These synthetic routes are classical and have been described inthe above-mentioned references of the prior art as well as in U.S. Pat.No. 4,818,096. The propargyl alcohols are either commercially availableor easily synthesized by the reaction of lithium acetylide or ethynyl(magnesium bromide) with the corresponding ketones (R₁)CO(R₂). Theketones are also either commercially available or easily synthesized bythe classical methods, for example, the Friedel-Crafts reaction from anacid chloride.

[0105] The derivatives of 1-naphthol are obtained by various methodsadapted from the literature. Below we give some references on methodsthat allow the synthesis of the compounds of the invention.

[0106] Method 1: Johnson et al. Org. React. 1951, Vol. 6, p. 1.

[0107] Method 2: U.S. Pat. No. 5,200,116 (Example 2) or U.S. Pat. No.6,207,084

[0108] The starting benzophenone in Method 1 can be prepared by thewell-known Friedel-Crafts acylation of dihydrobenzofuran with benzoylchloride, and the starting ketone in Method 2 can be prepared accordingto the procedure in U.S. Pat. No. 6,210,608.

[0109] To those skilled in the art, the alkoxycarbonyl group in thenaphthol (III) can be transformed into a variety of different groupsincluding methyl, hydroxymethyl, benzoyl, alkenyl, etc. For example,

[0110] In the reactions, DIBAL-H: diisobutoxyaluminum hydride, pTsOH:p-toluenesulphonic acid, MeOH: methanol.

[0111] Regarding the commercial application of compounds according tothe present invention, it should be noted that they can be used as aphotochromic material dispersed in the composition of a polymer matrix.They can also be used in solution.

[0112] A photochromic solution can be obtained by dissolving thecompound in an organic solvent, such as toluene, dichloromethane,tetrahydrofuran or ethanol. The solutions obtained are generallycolorless and transparent. When exposed to sunlight, they develop astrong coloration and they recover the color of this state when placedin an environment with lesser exposure to solar radiation or, in otherwords, when they are no longer exposed to UV radiation. In general, avery low concentration of products (on the order of 0.01-5% by weight orvolume) is sufficient to obtain an intense coloration.

[0113] The most interesting applications are those in which thephotochrome is dispersed uniformly within or on the surface of apolymer, copolymer or mixture of polymers. The implementation methodsthat can be considered are of a great variety. Among those known to aperson skilled in the art, one can cite, for example, diffusion in the(co)polymer, from a suspension or solution of the photochrome, in asilicone oil, in an aliphatic or aromatic hydrocarbon, in a glycol, orfrom another polymer matrix. Currently the diffusion is carried out at atemperature of 50-200° C. for a duration of 15 minutes to several hours,depending on the nature of the polymer matrix. Another implementationtechnique consists in mixing the photochrome in a formulation ofpolymerizable materials, in depositing this mixture on a surface or in amold and in then carrying out the polymerization. These implementationtechniques and others are described in the article by CRANO et al.“Spiroxazines and their use in photochromic lenses,” published inApplied Photochromic Polymer Systems, Publishers Blackie and Son Ltd.,1992. According to a variant of the invention, it is also possible toconsider grafting the photochromes onto (co)polymers. Thus, anotheraspect of the invention consists of the (co)polymers grafted with atleast one of the photochromes described above.

[0114] As examples of preferred polymer materials for opticalapplications of the photochromic compound according to the invention,one can mention the following products including, but not limited to:alkyl, cycloalkyl, aryl or arylalkyl poly(mono-, di-, tri-,tetra)acrylate or poly(mono-, di-, tri-, tetra) methacrylate, optionallyhalogenated or comprising at least ether and/or ester and/or carbonateand/or carbamate and/or thiocarbamate and/or urea and/or amide group;polystyrene, polycarbonate (e.g., bisphenol A polycarbonate,poly(carbonate of diallyl diethylene glycol), polyepoxy, polyurethane,polythiourethane, polysiloxane, polyacrylonitrile, polyamide, aliphaticor aromatic polyester, vinyl polymers, cellulose acetate, cellulosetriacetate, cellulose acetate-propionate or polyvinylbutyral, copolymersof two or more types of monomers or mixtures of the above-mentionedpolymers, preferably polycarbonate-polyurethane,poly(meth)acrylate-polyurethane, polystyrene-poly(meth)acrylate orpolystyrene-polyacrylonitrile, advantageously a mixture of polyesterand/or polycarbonate or poly(meth)acrylate.

[0115] In a particularly preferred manner, the photochromicnaphthopyrans of the invention are used in polyester or polyether typethermoplastic polyurethanes, two-part polyurethane adhesives.

[0116] The quantity of photochrome used in various articles depends onthe desired degree of darkening. In particular, it is used in a quantityof 0.01-10 wt % of the total weight of the layer in which thephotochrome is included. The photochromic compounds according to theinvention can be used alone or in a mixture with other products to forma composition that can be in solid or liquid form, for example, in asolution or in a dispersion, as has already been mentioned above. Thesecompositions, which constitute another object of the invention, cancomprise one or more compounds (I) according to the invention and othercomplementary photochromic compounds which allow the attaining of darkcolorations, for example, gray or brown, which the public desires inapplications such as ophthalmic or sun-protection eyewear. Theseadditional photochromic compounds can be those known to a person skilledin the art and described in the literature, for example, othernaphthopyrans, benzopyrans, chromenes (U.S. Pat. Nos. 3,567,605,5,238,981, World Patent No. 9,422,850, European Patent No. 562,915),spiropyrans or naphthospiropyrans (U.S. Pat. No. 5,238,981) andspiroxazines (CRANO et al., “Applied Photochromic Polyrmer Systems,”Publishers Blackie & Son Ltd., 1992, Chapter 2).

[0117] These compositions according to the invention can also comprise:

[0118] Non-photochromic dyes allowing the adjustment of the tint,

[0119] and/or one or more stabilizers, such as, for example, anantioxidant,

[0120] and/or one or more anti-UV screens,

[0121] and/or one or more anti[free]radical agents,

[0122] and/or deactivators that deactivate the states of photochemicalexcitation.

[0123] These additives can enable further improvements in the durabilityof said compositions.

[0124] According to another one of its aspects pertaining to theapplication of the photochromic compounds (I), the present inventionalso relates to ophthalmic articles, such as articles of ophthalmic orsun protection eyewear articles, or eye shields comprising at least onecompound according to the invention and/or at least one (co)polymerformed, at least in part, of repeating units derived from compoundshaving formula (I) and/or at least one composition comprising compounds(I) according to the invention, as defined above, and/or at least onematrix, as defined above, made of an organic polymer material or amineral material or a mineral-organic hybrid material incorporating atleast one compound of the invention.

[0125] In practice, the articles to which the present invention appliesmore particularly are photochromic ophthalmic or sun-protection lenses,glass paneling (glasses for buildings, for locomotion devices,automobiles), optical devices, decorative articles, sun-protectionarticles, information storage, etc.

[0126] The present invention will be better understood in the light ofthe following examples of synthesis and photochromic validation ofcompounds having the general formula (I). These examples are notintended to be interpreted as limiting the invention, but rather, showspecific aspects of the invention within the broad generic scopedisclosed.

EXAMPLES Example 1

[0127]

[0128] Step 1: To a reaction flask containing 2,3-dihydrobenzofuran(13.5 grams) and benzoyl chloride (16.6 grams) in 170 milliliters (mL)of methylene chloride were added anhydrous aluminum chloride (18.0grams) under nitrogen blanket over 40 minutes. The reaction temperaturewas controlled at around 25° C. with an ice/water bath. The reactionmixture was stirred at room temperature overnight. The resulting mixturewas poured into 150 mL of ice/water and stirred vigorously for 30minutes. The organic layer was separated, washed with water, dried overmagnesium sulfate. The methylene chloride solvent was removed by rotaryevaporation to give 25 grams of thick pink oil. It is used ‘as is’ inthe next step.

[0129] Step 2: The product from Step 1 (25 g), dimethyl succinate (21.0g), and potassium t-butoxide (16.5 g) were mixed in 250 ml of toluene.The mixture was refluxed for 2 hours under nitrogen blanket. After itwas cooled to room temperature, 200 ml of water was added and mixedwell. The aqueous phase was separated, acidified with 5N HCl, andextracted with 3×100 ml of ethyl acetate. The combined extracts werewashed once with water, dried over magnesium sulfate. The solvent wasremoved under reduced pressure to give 40.5 g of honey-like crudehalf-ester product. It was known that the crude product contains somealiphatic oil contaminants from the ethyl acetate solvent. It is usedwithout purification.

[0130] Step 3: The crude half-ester from Step 2 (40 g) was added toreaction flask containing 180 ml of acetic anhydride and 23 g ofanhydrous potassium acetate. The mixture was refluxed for 1.5 hours,cooled, filtered. The solid in the filtration funnel was washedthoroughly with ethyl acetate. The combined filtrate was concentrated tojust dry under vacuum. The dark solid was re-dissolved in ethyl acetateand washed with water, dried over magnesium sulfate. The organicsolution was concentrated under reduced pressure. The residual wassubjected to a silica column with ethyl acetate/hexane 1:4 as elutant.Two main portions were obtained: 8.7 g of light yellow solid, and 36 gof light brown thick oil. An NMR spectrum showed the light yellow solidto have a structure of Compound 1-3-p1:(2,3-dihydro-5-phenyl-6-methoxycarbonyl-8-acetoxy-naphtho[2,3-b]furan).The oil portion contains uncertain amount of Compound 1-3-p1 and its twoisomers Compound 1-3-p2 and Compound 1-3-p3, in ethyoxyethanol and methyisoamyl ketone Icontaminates from ethyl acetate solvent.

[0131] Step 4: The oil mixture from Step 3 (12 grams) was dissolved in70 ml of toluene and 10 g of p-toluenesulfonic acid was added. Thereaction solution is refluxed for 2 hours, cooled, washed with water,and concentrated to 21 grams of thick oil mixture.

[0132] Step 5: The mixture from Step 4 (14.5 grams) was reacted with 2.0g of 1,1-di(4-methoxyphenyl)-2-propyn-1-ol in 20 ml of toluene inpresence of catalytic amount of p-toluenesulfonic acid under reflux for3 hours. The reaction solution was cooled, concentrated. A silica columnwith ethyl acetate/hexane 1:4 as eluent provided three photochromiccompounds: 450 mg of 1-5-p1, 5 mg of 1-5-p2, and 500 mg of 1-5-p3.Proton NMR confirmed that Compound 1-5-p2 has the molecular structure ofthis example.

Comparative Example 1

[0133]

[0134] Proton NMR confirmed that Compound 1-5-p1 has the molecularstructure of this example.

Comparative Example 2

[0135]

[0136] Proton NMR confirmed that Compound 1-5-p3 has the molecularstructure of this example.

Example 2

[0137] Step 1: Compound 1-3-p1 from Step 3 of Example 1 (1.85 g) wasmixed with 50 ml of methanol and 1 ml of concentrated HCl. The mixturewas refluxed for 7 hours before it was cooled down to room temperature.100 ml of water was then added. The product was extracted with 200 mlether and followed by separation, drying over magnesium sulfate,filtering, and vacuum drying to yield 1.55 g of very light yellowpowder.

[0138] Step 2: The product of Step 1 (0.5 g) was dissolved in 10 ml ofTHF, and 4 ml of cyclopentylmagnesium bromide (2M in ether) was droppedin at room temperature. After stirring for 2 days, few mililiters of 1NHCl was added in. The mixture was extracted with toluene, dried overmagnesium sulfate, filtered, and concentrated to a solid paste. Thepaste was then washed with hexane to provide 0.64 g of off-white powder.

[0139] Step 3: The product from Step 2 (0.56 g) was mixed with 10 wt. %p-toluenesulfonic acid and 50 ml of toluene. The mixture was refluxedfor one and half hour, concentrated, and chromatographied with silicacolumn and 1:5 of EtOAc/Hexane as eluent. 0.08 g waxy solid wasobtained.

[0140] Step 4: The waxy solid was then reacted with1-phenyl-1-biphenyl-2-propyn-1-ol (0.1 g) in 15 ml of toluene andcatalytic amount of p-toluenesulfonic acid for 30 minutes at 50 to 80°C. After concentrated and purified by a silica column with 1:15 ethylacetate/hexane as eluent, the photochromic portion was re-crystallizedin petroleum ether to yield 60 mg of light brown powder. Its structurewas confirmed by NMR.

Example 3

[0141]

[0142] Step 1: Steps 2 and 3 of Example 2 were followed. except thatcyclopentylmagesium bromide was replace by n-butylmagnesium chloride (3Min ether). In this case, two products were obtained as Compound 3-1-a(0.08 g) and 3-1-b (0.15 g). They are light yellow waxy solid.

[0143] Step 2: Compound 3-1-b (0.12 g) was reacted with1,1-di(4-methoxyphenyl)-2-propyn-1-ol (0.24 g) in 20 ml of toluene andcatalytic amount of p-toluenesulfonic acid for 50 minutes at 50 to 80°C. After concentrated and purified by a silica column with 1:20 ethylacetate/hexane as eluent, 140 mg of white powder was obtained. Itsstructure was confirmed by NMR.

Example 4

[0144] Compound 3-1-a (0.08 g) was reacted with1,1-di(4-methoxyphenyl)-2-propyn-1-ol (0.1 g) in 10 ml of toluene andcatalytic amount of p-toluenesulfonic acid for 50 minutes at 30 to 80°C. After concentrated and purified by a silica column with 1:15 ethylacetate/hexane as eluent, 80 mg of light yellow powder was obtained. Itsstructure was confirmed by NMR.

[0145] Photochromic Property Measurement:

[0146] Each of the compounds was dissolved in a solution of athermoplastic polyurethane (20%) in THF to make a casting solutioncontaining 1 wt. % of the photochromic compound with respect to thepolyurethane. Photochromic polyurethane films of about 0.1 mm thick werethen prepared with the casting solutions on flat borosilicate glasspieces. After complete evaporation of solvent, the UV-visibleabsorptions are then measured before and after exposure the photochromicpolyurethane films to a 365 nm UV source. The photochromic properties:the wavelengths □_(A) and □_(B) of the two principle absorption bandsand relative induced optical density (RIOD, defined as the ratio ofinduced optical density between band A and band B) of these compoundsare given in the Table 1 below. TABLE 1 Compound □_(A) (nm) □_(B) (nm)RIOD Example 1 440 530 0.91 Example 2 420 530 1.85 Example 3 440 5401.54 Example 4 440 540 1.39 Comparative 430 538 0.76 Example 1Comparative 420 520 0.46 Example 2

[0147] The data presented in Table 1 show that each tested compound ofthe present invention has two absorption peaks in the visible spectrumand a relative induced optical density of greater than 0.80. The datademonstrates that a single compound of the present invention exhibits ablended activated hue. By employing a compound of the present inventionhaving two activated visible absorption maxima, fewer distinct compoundsare required to achieve a blend of activated visible absorption maximato produce the desired activated hue, e.g. neutral color. In addition,the blended activated hue of a compound of the present invention isparticularly suitable for use in photochromic articles having a brown ordriver activated color due to the greater optical density of Band A(420-500 nm) than the optical density of Band B (500-600 nm).

[0148] The present invention has been described with reference tospecific details of particular embodiments thereof. It is not intendedthat such details be regarded as limitations upon the scope of theinvention except insofar as to the extent that they are included in theaccompanying claims. All publications and patents referred to in thisapplication are hereby incorporated by reference.

What is claimed is:
 1. A naphthopyran compound of the following formula:

wherein (a) F is a 5- to 7-member saturated heterocyclic ring groupfused to i or j side of the naphthopyran ring and containing an oxygenatom directly connected to 7-, 8-, or 9-position; (b) R₆ represents ahydrogen, a C1-C6 alkyl, alkoxy, a —C(O)R group, wherein R is selectedfrom hydrogen, hydroxy, alkyl, alkoxy, an aryl or heteroaryl group whichcomprises in its basic structure (that is, in its ring atoms, the ringscomprising 5, 6 or 7 atoms) 6 to 24 carbon atoms or 4 to 24 carbon atomsrespectively and at least one heteroatom selected from sulfur, oxygenand nitrogen; the basic structure being optionally substituted with atleast one substituent selected from: a halogen atom (e.g., fluorine,chlorine and bromine), a hydroxy group, a linear or branched alkyl groupcomprising 1 to 12 carbon atoms, a linear or branched alkoxy groupcomprising 1 to 12 carbon atoms, a haloalkyl or haloalkoxy groupcorresponding to the (C1-C12) alkyl or alkoxy groups above respectivelywhich are substituted with at least one halogen atom, and notably afluoroalkyl group of this type, a linear or branched alkenyl groupcomprising 2 to 12 carbon atoms, and notably a vinyl group or an allylgroup, an —NH₂ group, an —NHR₈ group, R₈ representing a linear orbranched alkyl group comprising 1 to 6 carbon atoms, a

 group, in which R₉ and R₁₀, which are the same or different,independently representing a linear or branched alkyl group comprising 1to 6 carbon atoms, or representing (together with the nitrogen atom towhich they are bound) a 5- to 7-membered ring which can comprise atleast one other heteroatom selected from oxygen, sulfur and nitrogen,said nitrogen being optionally substituted with a group that is a linearor branched alkyl group comprising 1 to 6 carbon atoms, a methacryloylgroup or an acryloyl group, a polyether, polyamide, polycarbonate,polycarbamate, polyurea or polyester residue; (c) R₅ represents: ahydroxy, a halogen, and notably fluorine, chlorine or bromine, a linearor branched alkyl group which comprises 1 to 12 carbon atoms(advantageously 1 to 6 carbon atoms), a cycloalkyl group comprising 3 to12 carbon atoms, a linear or branched alkoxy group comprising 1 to 12carbon atoms (most advantageously 1 to 6 carbon atoms), a haloalkyl,halocycloalkyl, or haloalkoxy group corresponding to the alkyl,cycloalkyl, alkoxy groups above respectively, which are substituted withat least one halogen atom, notably selected from fluorine, chlorine andbromine, a linear or branched alkenyl or alkynyl group comprising 1-12carbon atoms, preferably a vinyl or allyl group, a linear or branchedalkenyloxy or alkynyloxy group comprising 1-12 carbon atoms, preferablyan allyloxy group, an aryl or heteroaryl group having the samedefinition as R₆ given supra, an aralkyl or heteroaralkyl group, thealkyl group, which is linear or branched, comprising 1 to 4 carbonatoms, and the aryl and heteroaryl groups having the same definitions asR6 given supra, an amine or amide group: —NH₂, —NHR₈, —CONH₂, —CONHR₈,

 R₈, R₉, and R₁₀ having their respective definitions given above for theamine substituents of the values R₆, a —C(R₁₁)₂X group, wherein X is—CN, halogen, hydroxy, alkoxy, benzoyloxy, C1-C6 acyloxy, amino, C1-C6mono-alklamino, C1-C6 dialkyl amino, morpholino, piperidino,1-indolinyl, pyrrolidyl, or trimethylsilyloxy, R₁₆ is hydrogen, C1-C6alkyl, phenyl or naphthyl with C1-C6 alkyl or C1-C6 alkoxy substituents,an —OCOR₁₂ or —COOR₁₂ group, R₁₂ representing a straight or branchedalkyl group comprising 1 to 6 carbon atoms, or a cycloalkyl groupcomprising 3 to 7 carbon atoms, or a phenyl group, optionallysubstituted with at least one of the substituents listed above withinthe values in the definitions of R₆, a methacryloyl group or an acryloylgroup, an epoxy group having the formula,

 in which k=1, 2or 3, a polyether, polyamide, polycarbonate,polycarbamate, polyurea or polyester residue; (d) R₁ and R₂, which areidentical or different, independently represent: a hydrogen, a linear orbranched alkyl group which comprises 1 to 12 carbon atoms (with orwithout substitution), a cycloalkyl group which comprises 3 to 12 carbonatoms, an aryl or heteroaryl group as R₆ defined supra, an aralkyl orheteroaralkyl group, the alkyl group, which is linear or branched,comprising 1 to 4 carbon atoms and the aryl and heteroaryl groups havingthe definitions given above, or the two substituents R₁ and R₂ togetherforming ring group such as those represented by an adamantyl, norbornyl,fluorenylidene, 5,5- or 10,10-di(C1-C6)alkylanthracenylidene, 5 (or10)-(C1-C6)alkyl-5 (or 10)-OH (or OR₁₅)anthracenylidene orspiro(C5-C6)cycloalkylanthracenylidene ring group; said ring group beingoptionally substituted with at least one of the substituents listedabove in the definitions for R₁, R₂; said ring group being optionallysubstituted with two adjacent groups that form a 5- to 6-member aromaticor non-aromatic ring which can comprise at least one heteroatom selectedfrom oxygen, sulfur, and nitrogen; (e) each R₇ group can be the same ordifferent, independently representing a hydrogen, a linear, branched, orcyclic alkyl group, a linear, branched, or cyclic alkoxy group, a linearor branched alkenyl or alkynyl group, a linear or branched alkenyloxy oralkynyloxy group, an aryl or heteroaryl group having the same definitionas that given supra for R₆, two of the R₇ groups, which are adjacent orbonded to the same carbon atom in the group F, form a 5- to 7-memberednon-aromatic ring which may comprise at least one hetroatom selectedfrom the group consisting of oxygen, sulfur, and nitrogen, and m is aninteger of 0 to
 6. 2. The naphthopyran compound according to claim 1,wherein: m and n are integers of 1 or 2, R′₁ and R′₂, same or different,represent a hydrogen, a linear, branched, or cyclic alkyl, an alkyoxywith the alkyl portion being linear, branched, or cyclic, anunsubstituted, mono- or di-substituted aromatic group, an aryloxy withthe aryl being unsubstituted, mono- or di-substituted; R₅ represents alinear, branched, or cyclic alkyl group, a linear or branched alkenyl oralkynyl group, a —C(R₁₁)₂X group, wherein X is hydroxy, alkoxy,benzoyloxy, C1-C6 acyloxy, an optionally substituted phenyl or benzylgroup, a —COR₁₂, or —COOR₁₂ group, R₁₂ representing a linear, branched,or cyclic alkyl group comprising 1 to 6 carbon atoms; R₆ represents aunsubstituted, mono- or di-substituted aromatic or hetero-aromatic groupselected from phenyl, naphthyl, pyridyl, furanyl, benzofuranyl, thenyl,benzothienyl; R₇ represents a hydrogen, a linear, branched, or cyclicalkyl group, a linear, branched, or cyclic alkoxy group, a linear orbranched alkenyl or alkynyl group, a linear or branched alkenyloxy oralkynyloxy group, an aryl or heteroaryl group having the same definitionas that given supra for R₆, two of the R₇ groups, which are adjacent orbonded to the same carbon atom in the group F, form a 5- to 7-memberednon-aromatic ring which may comprise at least one hetroatom selectedfrom the group consisting of oxygen, sulfur, and nitrogen, and m is aninteger of o to
 2. 3. The naphthopyran compound according to claim 1,being further crosslinked.
 4. The naphthopyran compound according toclaim 1, being further polymerized.
 5. A photochromic compositioncomprising: at least one compound according to claim 1; at least onelinear or cross-linked (co)polymer which contains, in its structure, atleast one compound according to claim 1; at least one additionalphotochromic compound of another type; at least one non-photochromiccoloring agent; and at least one stabilizing agent.
 6. The naphthopyrancompound according to claim 1 being further incorporated into a(co)polymer matrix.
 7. The naphthopyran compound according to claim 5being further incorporated into a (co)polymer matrix.
 8. A (co)polymermatrix comprising at least one co(polymer) and/or reticulate accordingto claim
 4. 9. A (co)polymer matrix according to claim 6 furthercomprising one or more (co)polymer selected from the group consistingof: an alkyl, cycloalkyl, (poly or oligo)ethylene glycol or aryl orarylalkyl mono-, di-, tri-, or tetraacrylate or mono-, di-, tri-, ortetramethacrylate which is optionally halogenated or which optionallycomprises at least one ether and/or ester and/or carbonate and/orcarbamate and/or thiocarbamate and/or urea and/or amide group;polystyrene, polyether, polyester, polycarbonate, polycarbamate,polyepoxy, polyurea, polyurethane, polythiourethane, polysiloxane,polyacrylonitrile, polyamide, aliphatic or aromatic polyester, vinylicpolymers, cellulose acetate, cellulose triacetate, celluloseacetate-propionate, polyvinylbutyral, poly(methyl methacrylate),poly(ethylene glycol bismethacrylate), poly(ethoxylated bisphenol Adimethacrylate), poly(vinyl acetate), polyvinylbutyral, polyurethane,polyanhydride and polymers of members of the group consisting ofdiethylene glycol bis(allyl carbonate) monomers, diethylene glycoldimethacrylate monomers, ethoxylated phenol bismethacrylate monomers,diisopropenyl benzene monomers and ethoxylated trimethylol propanetriacrylate monomers.
 10. The naphthopyran compound according to claim 1being further incorporated into an ophthalmic lens.
 11. The naphthopyrancompound according to claim 5 being further incorporated into anophthalmic lens.
 12. The naphthopyran compound according to claim 3being further incorporated into an ophthalmic lens.
 13. The naphthopyrancompound according to claim 6 being further incorporated into anophthalmic lens.
 14. The naphthopyran compound according to claim 9being further

incorporated into an ophthalmic lens.
 15. A naphthopyran compound of thefollowing formula: in which, R′₁, R′₂, and R′₆, same or different,represent a linear, branched, or cyclic alkyl group, an alkyoxy groupwith the alkyl portion being linear, branched, or cyclic; R₅ representsa linear, branched, or cyclic alkyl group, a linear or branched alkenylor alkynyl group, a —C(R₁₁)₂X group, wherein X is hydroxy, alkoxy,benzoyloxy, C1-C6 acyloxy, R₁₁ is hydrogen or C1-C6 alkyl; ansubstituted phenyl or benzyl group, a —COR₁₂, or —COOR₁₂ group, R₁₂representing a linear, branched, or cyclic alkyl group comprising 1 to 6carbon atoms, or an substituted phenyl or benzyl group.